Khan Ilyas, Khan Waqar A, Qasim Muhammad, Afridi Idrees, Alharbi Sayer O
Faculty of Mathematics and Statistics, Ton Duc Thang University, Ho Chi Minh City 700,000, Vietnam.
Department of Mechanical Engineering, College of Engineering, Prince Mohammad Bin Fahd University, Al Khobar 31952, Saudi Arabia.
Entropy (Basel). 2019 Jan 16;21(1):74. doi: 10.3390/e21010074.
This article is devoted to study sustainability of entropy generation in an incompressible thermal flow of Newtonian fluids over a thin needle that is moving in a parallel stream. Two types of Newtonian fluids (water and air) are considered in this work. The energy dissipation term is included in the energy equation. Here, it is presumed that (the free stream velocity) is in the positive axial direction (-) and the motion of the thin needle is in the opposite or similar direction as the free stream velocity. The reduced self-similar governing equations are solved numerically with the aid of the shooting technique with the fourth-order-Runge-Kutta method. Using similarity transformations, it is possible to obtain the expression for dimensionless form of the volumetric entropy generation rate and the Bejan number. The effects of Prandtl number, Eckert number and dimensionless temperature parameter are discussed graphically in details for water and air taken as Newtonian fluids.
本文致力于研究牛顿流体在平行流中移动的细针上的不可压缩热流中熵产生的可持续性。本研究考虑了两种类型的牛顿流体（水和空气）。能量方程中包含了能量耗散项。在此，假定（自由流速度）沿正轴向方向（-），且细针的运动方向与自由流速度方向相反或相同。利用四阶龙格 - 库塔方法，借助打靶技术对简化的自相似控制方程进行了数值求解。通过相似变换，可以得到体积熵产生率和贝扬数的无量纲形式的表达式。以水和空气作为牛顿流体，详细地以图形方式讨论了普朗特数、埃克特数和无量纲温度参数的影响。
